Enable LD_PRELOAD on Linux for Harmony mods by default (launcher)

[hhyyrylainen]

Once we have testing info that the new LD_PRELOAD works (and hopefully doesn't break the game on anyone's system), it should be made a default option as right now it is opt-in.

Old issue about it being implemented: #6486

[hhyyrylainen]

And just to clarify while this issue is in the Thrive repo, this feature should actually be done in the launcher: https://github.com/Revolutionary-Games/Thrive-Launcher

PR adding the LD_PRELOAD option support: Revolutionary-Games/Thrive-Launcher#976

For testing this, I think the example mods need to be updated and recompiled: https://github.com/Revolutionary-Games/ThriveMods